I have two multiple choice questions Q1 and Q2.
For each of them I have more than 20 checkboxes.
Each checkbox of Q1 has a score of 3 (in my mind) and every checkbox of Q2 has a score of 6.

I need the final score to be exactly 51 (sum of 3*number of checks in Q1 + 6*number of checks in Q2). So I set up an equation question with the expression:
Would you guide me in the process of setting a condition such that if the score of equation is not exactly 51 the survey will not proceed?

I tried read forums and the manual, but still is not clear to me how to do.
I'm new to LimeSurvey so I will really appreciate your help!
Thanks a lot!

Assuming question codes "Q1" and Q2" and both questions are on the same screen, something like this in the Question validation equation for both questions:
And, this for the Question validation tip:
If the questions are on separate pages, place those in Q2 only.

Sample survey attached:

Thanks a lot!
It works if I test the survey you sent, but it doesn't if I put it on my survey...
The prompt and the numbers selected are shown correctly. However, with the correct score I cannot proceed...

Can you help me figure out why?

Thanks again

You have relevance on those questions which may mess things up but try adding .NAOK:


And:

Thanks. This doesn't change things, but thanks to your answer I noticed that the relevance equation got automatically transformed into something strange.

This was the relevance equation I originally set up: Then for some question it was automatically changed into:
Having fixed that, now everything works!
I don't know if this is the place, but perhaps the automatic change is a bug we can signal.

andreafc wrote: noticed that the relevance equation got automatically transformed into something strange.

The strange something is the SQGA identifier.
www.limesurvey.org/manual/SGQA_identifier